Vehicle seat assembly

ABSTRACT

A vehicle seat assembly comprising a cushion and a backrest forwardly swingable over the cushion. A two-stage latch mechanism interposed between the cushion frame structure and a backrest support arm includes a control lever operable for first stage release of the latch mechanism to unlock the backrest for forward tilting movement and further operable for second stage release of the latch mechanism sequentially of the first stage to permit angular adjustment of the backrest.

United States Patent Inventors Lloyd R. Vivian Bi Karl Budde, Detroit,Mich. Appl. No. 832,686 Filed June 12, 1969 Patented Apr. 27, 1971Assignee Ford Motor Company Deal-born, Mich.

VEHICLE SEAT ASSEMBLY 9 Claims, 7 Drawing Figs. US. 297/383, 297/379,297/369, 248/393 Int. Cl A47c 3/00, B60n 1/02 FieldofSearch 297/383,

[56] References Cited UNITED STATES PATENTS 1,685,770 10/1928 Bowen297/383X 2,272,980 2/1942 McLellan et al. 297/383X 2,678,680 5/ l 954Haltenberger 297/383 2,678,681 5/1954 -laltenberger 297/ 3 83X 2,730,l62 1/1956 Davis 297/383X Primary Examinerlaul R. Gilliam Attorney-JohnR. Faulkner and John J. Roethel ABSTRACT: A vehicle seat assemblycomprising a cushion VEHICLE SEAT ASSEMBLY BACKGROUND OF THE INVENTIONthe seat cushion to the front surface of the backrest isnonadjustable.Because of this many persons do not feel they have proper underkneesupport. The seat length in a fore and aft direction is either too longor too short for the length of their legs.

A person with short legs can somewhat alleviate this condition byplacing an auxiliary cushion behind their back so that in effect theysit closer to the front edge of the seat. The person withlong legscannot do much about the situation.

It has been proposed in the prior art to mount the seat backrest forfore and aft adjustment relative to the seat cushion or seat bottom.Exemplary prior art patents include US. Pat. No. 2,121,238 and US. Pat.No. 2,678,680.

It is an object of the present invention to adapt the variable seatbackrest positioning concept to a vehicle seat assembly in which theseat backrest is forwardly tiltable over the seat cushion to facilitateingress to or egress from the rear passenger area of a typical two doorsedan.

If the backrest is to be forwardly tiltable, the seatsupportingmechanism under current vehicle regulations must incorporate a latch forholding the backrest in its normal upright position. Accordingly, it isa further object of the present invention to include such a latch in thevariable position backrest mechanism.

SUMMARY OF THE INVENTION angle lock, and for controlling backrest angleadjustment.

As used herein, backrest angle lock refers to the holding or positioningof the backrest in the upstanding position to which it is returnableafter having been tilted forwardly.

It is through the control of the backrest angle adjustment that thevariable length seat concept is achieved. The twostage latch mechanismhas a control lever first operable to release a first stage of the latchmechanism to unlock the backrest for forward tilting movement about thepivot means and further operable to release a second stage of the latchmechanism sequentially of the first stage release to pennit angularadjustment of the backrest through a limited range of movement relativeto the seat cushion.

DESCRIPTION OF THE DRAWINGS Other objects, advantages and features ofthe present invention can be made more apparent as this descriptionproceeds reference being had to the accompanying drawings, wherein:

FIG. 1 is a side elevation of a vehicle seat assembly embodying thepresent invention with part of the vehicle floor being shown in section;

FIGS. 2 and 3 are section views on the lines 2-2 and 3-3 FIG. 1,respectively;

FIG. 4 is a section view on the line 4-4 of FIG. 1 illustratingsymmetrical components at the sides of the seat assembly; and

FIGS. 5, 6 and 7 are section views on the lines 5-5, 6-6 and 7-7,respectively.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings, andmore particularly to FIG. 1, there is illustrated a vehicle seatassembly, generally designated 11, adapted to be mounted on a floor 12of a passenger compartment of a vehicle body. The seat assembly 11comprises a seat cushion 13 which is carried on a tubular seat framestructure 14 having front and rear members 15 and 16, respectively, andside members 17 and 18.

It will be understood that the seat cushion frame structure 14 may befixedly supported on the vehicle floor 12 or that it may be supported ona seat track mechanism such as disclosed in US. Pat. No. 3,001,835. Itis only necessary that the frame structure 14 be supported at a highenough level to accommodate a pair ofdepending brackets 19, one of whichis welded or otherwise secured to each side frame member 117 and 18.

The seat assembly includes a backrest member 21 having depending sidesupport arms 22. At their lower ends the depending side support arms 22are pivotally supported on shoulder studs 23 joumaled in the lower endsof the brackets 19. The backrest 21 thus is mounted for swingingmovement about a pivot axis defined by the shoulder studs 23 from itsnormal upstanding position indicated in FIG. 1 to a forwardly inclinedposition.

Interposed between one of brackets 19, preferably an outboard bracket,and the contiguous depending side support arm 22 is a latch mechanism,generally designated 24. The latch mechanism 24 has a dual function.First, it controls the backrest 21 angle lock, i.e., it holds thebackrest in its upstanding position against swinging movement forwardlyover the seat cushion 13. Such an angle lock or latching function isrequired so that the backrest cannot be thrown in a forward directionevery time the vehicle is rapidly decelerated by the sudden or hardapplication of its brakes or if the misfortune of an impact stop shouldoccur.

The latch mechanism 24 has a second function of.

controlling backrest angle adjustment. By this is meant the position ofthe backrest relative to the front edge of the seat cushion. Adjustmentof this position permits the seat occupant to adjust the depth of theseat so that proper underknee support can be obtained. A person having ashort knee to hip dimension would want the backrest positioned closer tothe front edge of the seat than would a taller person having a longerknee to hip dimension.

The first or backrest angle lock function of the latch mechanism 24 isachieved through a first detent means comprising an abutment 25 carriedon a control plate 26 and a coacting abutment 27 formed on a controllever 28.

The control plate 26 is a substantially triangular member pivotallysupported at its apex, its lower end, on the shoulder stud 23 betweenthe depending side arm 22 and the bracket 19, see FIGS. 2, 4 or 6. Theabutment 25 projects out of the plane of the plate 26 on the bracket 19side.

The control lever 28 is an elongated curved member that is pivotallymounted on the upper rear corner of the bracket 19 on a pivot stud 29.The forward or left end 31, as viewed in FIG. 1, of the lever 28 has aninwardly projecting tab 32, see FIG. 7. The tab is apertured to receiveone end 33 of a tension spring 34 booked at its other end 35 in anaperture in the bracket 19. Tension spring 34 maintains the lower edge36 of lever 28 in engagement with the abutment 25.

The control lever 28 is swingable about the pivot stud 29 against theresistance of spring 34 by manipulation of a handle 37, as will be morefully explained.

A control plate 26 is coupled to the depending side arm 22 of thebracket 21 by a stiff tension spring 38. The forward or left end 39 ofthe spring 38, as viewed in FIG. 1, engages an apertured tab 41projecting outwardly from the plane of the control plate 26 (see FIG.6). The rear or right end 42 of the spring 38 is hooked over a stud 43anchored in the depending backrest side arm 22.

Because of the weight of the backrest 21 and its offcenter relationshipto the pivot axis defined by the pivot studs 23, the spring 38 biasesthe control plate 26 in a clockwise direction, as viewed in FIG. 1. Astop or abutment 44 welded on the bracket 19 at its rear edge is engagedby the edge 45 of the control plate 26 to limit such clockwise biasingaction.

It is necessary, however, that the control plate 26 and the dependingside arm 22 be movable relative to one another to achieve the secondaryfunction of the latch mechanism 24, i.e., the backrest angle adjustmentfunction in which the seat back 21 may be positioned selectivelyrelative to the front edge of the cushion 13. As best seen in FIG. 1, apawl 46 is pivotally mounted on the pivot stud 43 secured to thedepending side arm 22. The pawl 46 has a series of teeth 47 meshing witha series of teeth 48 radially carried on the upper end of the controlplate 26.

The pawl 46 is urged in counterclockwise direction, as viewed in FIG. 1,about pivot stud 43 by a spring 49 which is tensioned between an end 51of pawl 46 and a tank 52 projecting from the support arm 22. At itsforward end, the pawl 46 has a tab 53 which extends from the plane ofthe pawl 46 and projects through an arcuate slot 54 in the control leverOPERATION Referring to FIG. 1, the backrest 21 is shown positioned inits rearmost position relative to the front edge of the seat cushion 13.lt is held by the latching mechanism 24 against forward tilting movementover the cushion 13.

if it is desired to tilt the backrest 21 forwardly to permit ingress toor egress from the vehicle passenger compartment seating area rearwardlyof the seat 13, this can be done by releasing the first stage of thelatch mechanism 24. This first stage release is obtained by lifting thehandle 37 of the control lever 28 a sufiicient distance so that itsabutment 27 will be out of the path of the abutment 25 of the controlplate 26. There is then nothing blocking forward swinging movement ofthe backrest 21 support arms 22 about the pivot axis defined by thepivot studs 23.

Upon return of the backrest 21 to its normal upstanding position, thecontrol lever 28 under influence of the spring 34 again will drop intothe P10. 1 position in which the abutments 27 and 25 are in abuttingrelationship. The backrest again will be latched against forward tiltingmovement.

Should it be desired to adjust the backrest 21 angle so that thebackrest in efiect is moved closer to the front edge of the cushion 13to accommodate a person having a shorter knee to hip dimension, thetwostage release operation of the latch mechanism must be brought intoplay.

The two-stage operation is accomplished by raising the handle 37 throughand beyond the first stage position or the position in which theabutments 27 and 25 are immediately out of alignment. Movement of thehandle 37 beyond this first stage position results in the control lever28 being swung to a position in which the lower edge 55 of the slot 54abuts the tab 53 on the end of the pawl 46. Further upward movement ofthe control lever 28 beyond this point results in the teeth 47 on thepawl 46 being lifted from the teeth 48 on the control plate 26.

The force exerted on the control plate 26 by the spring 38 holds controlplate against the abutment 44 on the bracket 19. If forward pressure isapplied to the backrest, the disengaged pawl 46 will be movable relativeto the control plate within a range extending between the position shownin FIG. 1 to a position in which the tab 53 abuts the edge 56 of theextension carrying the tab 41 on the control plate. Release of thehandle 37 at any position within the range of movement of the pawlrelative to the control plate results in reengagement of the teeth 47 onthe pawl 46 with the teeth 48 on the control plate 26.

As will be readily apparent, the position of engagement of the pawl 46with the control plate 26 determines the at rest position of thebackrest relative to the seat cushion since the at rest position of thecontrol plate 26 relative to the seat cushion is always determined bythe relationship of its edge 45 relative to the stop or abutment 44.

As soon as the pawl 46 is locked to the control plate 26, spring 34which is relatively much weaker than the spring 38 is able to functionto return the control lever 28 to the position in which the abutments 27and 25 are again in alignment thus latching the backrest against forwardtilting movement relative to the seat cushion 13 until such time as thehandle 37 is lifted sufficiently to move the abutments 27 and 25 out ofalignment with each other.

it will be understood that the invention is not to be limited to theexact construction shown and described but that various changes andmodifications may be made without departing from the spirit and scope ofthe invention.

We claim:

1. A vehicle seat assembly comprising:

a seat cushion supported on a frame structure,

a backrest having depending support arms at each side thereof,

pivot means pivotally supporting the support arms in juxtaposition tothe seat cushion for forwardly swingable movement of the backrestbetween an upstanding position and a forwardly inclined position,

and a two-stage latch mechanism interposed between the frame structureand one of the support arms controlling backrest angle lock and backrestangle adjustment,

the latch mechanism having a control lever pivotally supported on theseat cushion frame structure and operable to release the first stage ofthe latch mechanism to permit angular adjustment of the backrest overthe seat cushion through a limited range of movement,

a control plate interposed between the frame structure and the onesupport arm for pivotal movement about the pivot means supporting thelatter,

the first stage of the latch mechanism comprising a detent means engagedwith a first part of the control plate and the second stage a pawl meansengaged with a second part of the control plate,

the detent means being integral with the control lever so that movementof the latter to a predetermined position results in disengagement ofthe detent means from the first part of the control plate whereby thebackrest is unlocked for full forward tilting movement,

the pawl means being independently pivotally supported on the supportarm and engageable by the control lever upon movement of the latterbeyond the detent means disengagement position,

the pawl means upon engagement by the control lever being disengagedfrom the second part of the control plate whereby the backrest supportarm and thereby the backrest can be moved relative to the control plateto change the backrest adjustment angle.

2. A vehicle seat assembly comprising:

a seat cushion,

a frame structure for the seat cushion having depending brackets at thesides thereof,

a backrest having depending support arms at each side thereof,

pivot means pivotally coupling the support arms to the brackets,

the backrest being swingable about the pivot axis of the pivot meansfrom an at rest upstanding position to a forwardly inclined positionover the seat cushion,

a latch mechanism interposed between one of said brackets and anadjacent one of the support arms,

the latch mechanism having a detent means controlling backrest anglelock and a pawl means controlling backrest angle adjustment,

the latch mechanism having a single control lever pivotally supported onthe one bracket for swinging movement and a control plate interposedbetween the one bracket and the one support arm,

the control plate being pivotal about the pivot means coupling the onesupport arm to the one bracket,

detent means for controlling the backrest angle lock comprises coactingabutments on control plate and control lever which when in abuttingrelation to each other restrain forward swinging movement of thebackrest about its pivot axis,

the control .lever being operable to release the detent means to unlockthe backrest for forward tilting movement or to release the pawl meanssequentially of the release of the detent means to permit backrest angleadjustment,

and stop means restricting movement of said backrest rearwardly oversaid seat cushion.

3. A vehicle seat assembly according to claim 2, in which:

the pawl means for controlling the backrest angle adjustment comprises apawl pivotally mounted on the one support arm coacting with a circularsegment of the control plate,

the pawl and the control plate circular segment having interlockingabutment portions which when interlocked prevent relative movement ofthe support arm and control plate thereby maintaining the backrest at aselected angle of adjustment.

4. A vehicle seat assembly according to claim 3, in which:

the stop means comprises an abutment carried on the one bracket coactingwith the control plate,

and the control plate when held between the control lever abutment andthe bracket abutment preventing movement of the backrest forwardly overthe seat cushion or rearwardly beyond a predetermined upright position.

5. A vehicle seat assembly according to claim 2, in which:

the pawl means for controlling the backrest angle adjustment comprises apawl pivotally mounted on the one support arm coacting with a circularsegment of the control plate,

the pawl and circular segment having engageable teeth 'which whenengaged prevent relative movement of the support arm and control platethereby maintaining the backrest at a preselected angle of adjustmentwhen in an upstanding position,

the control lever upon being swung to a first position to release thefirst detent means causing disengagement of the coacting abutment on thecontrol plate and control lever whereby the backrest is swingable aboutthe support arm pivot means to a forwardly tilted position over the seatcushion,

the control lever upon being swung beyond the first position to a secondposition further causing disengagement of the pawl from the circularsegment teeth whereby the pawl, and therefor the support arm carryingthe latter, are shiftable for backrest angle adjustment.

6.- A vehicle seat assembly according to claim 5, in which:

the stop means comprises an abutment carried on the one bracket coactingwith the control plate,

the control plate is held between the control lever abutment and thebracket abutment to prevent movement of said backrest forwardly oversaid seat cushion or rearwardly beyond a predetermined upright position.

7. A vehicle seat assembly according to claim 6 in which a tensionspring extends between the control plate and the support arm to maintainthe control plate, the pawl and the bracket abutment in biasedrelationship to one another.

8. A vehicle seat assembly according to claim 7, in which a tensionspring extends between the one support arm and a part of the pawl tourge the latter in circular segment engagement direction.

9. A vehicle seat assembly according to claim 8, in which a tensionspring extends between the one b4acket and the control lever to urge thelatter in bracket abutment engaging direction.

1. A vehicle seat assembly comprising: a seat cushion supported on aframe structure, a backrest having depending support arms at each sidethereof, pivot means pivotally supporting the support arms injuxtaposition to the seat cushion for forwardly swingable movement ofthe backrest between an upstanding position and a forwardly inclinedposition, and a two-stage latch mechanism interposed between the framestructure and one of the support arms controlling backrest angle lockand backrest angle adjustment, the latch mechanism having a controllever pivotally supported on the seat cushion frame structure andoperable to release the first stage of the latch mechanism to permitangular adjustment of the backrest over the seat cushion through alimited range of movement, a control plate interposed between the framestructure and the one support arm for pivotal movement about the pivotmeans supporting the latter, the first stage of the latch mechanismcomprising a detent means engaged with a first part of the control plateand the second stage a pawl means engaged with a second part of thecontrol plate, the detent means being integral with the control lever sothat movement of the latter to a predetermined position results indisengagement of the detent means from the first part of the controlplate whereby the backrest is unlocked for full forward tiltingmovement, the pawl means being independently pivotally supported on thesupport arm and engageable by the control lever upon movement of thelatter beyond the detent means disengagement position, the pawl meansupon engagement by the control lever being disengaged from the secondpart of the control plate whereby the backrest support arm and therebythe backrest can be moved relative to the control plate to change thebackrest adjustment angle.
 2. A vehicle seat assembly comprising: a seatcushion, a frame structure for the seat cushion having dependingbrackets at the sides thereof, a backrest having depending support armsat each side thereof, pivot means pivotally coupling the support arms tothe brackets, the backrest being swingable about the pivot axis of thepivot means from an at rest upstanding position to a forwardly inclinedposition over the seat cushion, a latch mechanism interposed between oneof said brackets and an adjacent one of the support arms, the latchmechanism having a detent means controlling backrest angle lock and apawl means controlling backrest angle adjustment, the latch mechanismhaving a single control lever pivotally supported on the one bracket forswinging movement and a control plate interposed between the one bracketand the one support arm, the control plate being pivotal about the pivotmeans coupling the one support arm to the one bracket, detent means forcontrolling the backrest angle lock comprises coacting abutments oncontrol plate and control lever which when in abutting relation to eachother restrain forward swinging movement of the backrest about its pivotaxis, the control lever being operable to release the detent means tounlock the backrest for forward tilting movement or to release the pawlmeans sequentially of the release of the detent means to permit backrestangle adjustment, and stop means restricting movement of said backrestrearwardly over said seat cushion.
 3. A vehicle seat assembly accordingto claim 2, in which: the pawl means for controlling the backrest angleadjustment comprises a pawl pivotally mounted on the one support armcoacting with a circular segment of the control plate, the pawl and thecontrol plate circular segment having interlocking abutment portionswhich when interlocked prevent relative movement of the support arm andcontrol plate thereby maintaining the backrest at a selected angle ofadjustment.
 4. A vehicle seat assembly according to claim 3, in which:the stop means comprises an abutment carried on the one bracket coactingwith the control plate, and the control plate when held between thecontrol lever abutment and the bracket abutment preventing movement ofthe backrest forwardly over the seat cushion or rearwardly beyond apredetermined upright position.
 5. A vehicle seat assembly according toclaim 2, in which: the pawl means for controlling the backrest angleadjustment comprises a pawl pivotally mounted on the one support armcoacting with a circular segment of the control plate, the pawl andcircular segment having engageable teeth which when engaged preventrelative movement of the support arm and control plate therebymaintaining the backrest at a preselected angle of adjustment when in anupstanding position, the control lever upon being swung to a firstposition to release the first detent means causing disengagement of thecoacting abutment on the control plate and control lever whereby thebackrest is swingable about the support arm pivot means to a forwardlytilted position over the seat cushion, the control lever upon beingswung beyond the first position to a second position further causingdisengagement of the pawl from the circular segment teeth whereby thepawl, and therefor the support arm carrying the latter, are shiftablefor backrest angle adjustment.
 6. A vehicle seat assembly according toclaim 5, in which: the stop means comprises an abutment carried on theone bracket coacting with the control plate, the control plate is heldbetween the control lever abutment and the bracket abutment to preventmovement of said backrest forwardly over said seat cushion or rearwardlybeyond a predetermined upright position.
 7. A vehicle seat assemblyaccording to claim 6 in which a tension spring extends between thecontrol plate and the support arm to maintain the control plate, thepawl and the bracket abutment in biased relationship to one another. 8.A vehicle seat assembly according to claim 7, in which a tension springextends between the one support arm and a part of the pawl to urge thelatter in circular segment engagement direction.
 9. A vehicle seatassembly according to claim 8, in which a tension spring exTends betweenthe one b4acket and the control lever to urge the latter in bracketabutment engaging direction.